Computer systems typically include a large number of computer components. The components need to be working properly in order to ensure the successful, continuous operation of the computer system. Power supply units (PSUs) have unique roles in computer systems because PSUs provide power and also include an attached cooling fan to circulate air over heat-producing components in the computer system. Although the PSU's cooling fan is typically weaker than other fans in the computer system, but the PSU's cooling fan can still provide crucial cooling. For example, in some computer systems, the failure of a PSU or the PSU's fan has been known to cause damage due to overheating. Therefore, it is extremely important to the functionality of a computing system that a PSU is quickly restored to operation (particularly its fan) if it fails to function properly.
The placement of a PSU can affect the ability to restore functionality of the PSU. For example, in a first typical configuration, the PSU and its fan can be placed along the exterior edge of the computer system while stronger system fans are placed in front of or behind the PSU fan. In second typical configuration, the PSU and its fan can be placed in parallel with the stronger system fans. The second configuration can be problematic for PSU fans because the stronger system fans can cause a reverse air current through the weaker PSU fans. For example, if the PSU fan is operating at less than full capacity or fails for any reason, air can be pulled between the blades of the PSU fan and pulled through the input of the stronger fan. This can cause the weaker PSU fan to slow down, cease operating, fail to restart, and even rotate in the incorrect direction.
Although the first configuration can be implemented in many computer systems, other computer systems can require the second configuration due to space, shape, sizing, and wiring restrictions for the computer components in such computer systems.
In view of the foregoing, systems and methods are needed to detect when a PSU in a computer system is not operating properly and to enable the PSU to return to normal operation, i.e., so that that a cooling fan in the PSU can return to having an adequate operating speed and providing a correct airflow direction.